Writing instrument



May 2, 1950 K. s. PARKER WRITING INSTRUMENT Filed March 22, 1945 IN VENTOR.

Patented May 2, 1950 UNITED STATES PATENT OFFICE WRITING INSTRUMENTKenneth S. Parker, Janesville, Wis., assigner to The Parker Pen Company,Janesville, Wis., a corporation of Wisconsin Application March 22, 1945,Serial No. 584,054

Claims.

The invention relates generally to writing instruments utilizing ink andmore particularly to. a writing instrument of the ball-point type.

The general object of the invention is to provide a novel ball-pointwriting instrument having an ink container of a resilientself-collapsible construction and adapted to feed ink therefrom to theball point under a slight pressure by virtue of the resilient collapsingeffort exerted by the container on the ink contained therein.

Another object is to provide a novel ball-point Writing instrumenthaving an ink containing sac of resilient material formed so that ittends to assume a collapsed state, the sac being adapted to be distendedby the ink therein and by its resilience to force the ink from the sacto the ball point.

A further object is to provide a rell for a writing instrument of theforegoing character, the refill being adapted to be inserted into thebarrel of the writing instrument and comprising a self-collapsing inksac enclosed within the barrel and in communication with the ball pointto feed ink thereto.

Still another object is to provide a refill for a Writing instrument ofthe foregoing character, which is in the form of a cartridge comprisinga self-collapsing sac for the ink, enclosed Within a casing, thecartridge being readily insertible in the barrel of the writinginstrument and secured i1'.-

therein in a manner to effect the feeding of ink. to the ball point bythe collapsing of the sac.

A still further object is to provide an inlr cartridge comprising a sacmade of resilient material and provided at one end with a dischargeorifice which tends to remain closed by the resilient character of thematerial to retain the ink therein.

Another object is to provide an ink cartridge comprising a rigid casingenclosing a sac made of resilient material and provided with an orifice,and a removable cap for the casing providing a closure for the orice ofthe sac to prevent ink from being discharged therefrom during handling.

Other objects and advantages will become apl parent from the followingdescription, taken in connection with the accompanying drawings, inwhich:

Figure l is a longitudinal sectional view of one form of ball-pointWriting instrument embodying, the features of the invention.

Fig. 2 is a longitudinal sectional view, on an enlarged scale, of an inkcartridge adapted to be used in the Writing instrument shown in Fig. 1and showing the cartridge empty.

Fig. 3 is a transverse sectional View taken on the line 3-3 of Fig. 2.

Fig. 4 is a view similar to Fig. 2, but showing the cartridge filledwith ink.

Fig. 5 is a view similar to Fig. 4 except illustrating a closure capapplied to the front end of the cartridge.

Fig. 6 is a transverse sectional view taken on the line 6 6 of Fig. 4.

Fig. 7 is an enlarged longitudinal sectional View of the front end ofthe writing instrument shown in Fig. 1.

In an instrument of the type shown, the writing element, adapted tocontact the writing surface, is a small ball IU which is caused torotate by such contact and Which carries a film of ink on its surfaceadapted to adhere to the writing surface as the ball I0 rolls thereon.The ball is mounted in a socket in the tip portion II of the writinginstrument and ink is supplied to the portion of the ball lying withinthe socket by means of a suitable ink feed passage I2. The ink feedpassage I 2 communicates with a reservoir located within a barrel orcasing I3 which is secured to the tip I I as by being threaded on areduced shank I8 of the tip. Writing instruments of this character areadapted to utilize an ink which is relatively thick and viscous.

The ball I0 is so mounted in its socket in the tip I I that no leakagearound the ball occurs, and ink may be withdrawn from the instrumentsolely in the form of a lm on the surface of the ball carried out of thetip by the rotation of the ball. In the present instance, the inventionis not limited to any particular form of socket for the ball nor for anyparticular form of feed passage.

To eiect a uniform supply of ink to the ball, the ink may be fed theretounder slight pressure. To this end the reservoir is in the form of a sacI4 of circular form in communication with the feed passage I2. The sacis made of a resilient material such as rubber or the like, and isformed so as to be self-collapsing. Thus, the resilience of the materialwhen ink is in the sac places the ink within the sac under a slightpressure, and the supply of ink therein, which tends to hold the sac inits distended form, is forced through the passage I2 to the ball III.

In its preferred form, the sac I4 constitutes the ink containing elementof an ink cartridge or refill. The cartridge preferably` comprises, inaddition to the sac I4, a rigid casing I5 of generally tubular formsurrounding the sac I4 `to lthickened Vportion I6.

protect it in handling. In order to retain the sac I4 within the tubularcasing I5, the iront or open end of the sac is enlarged as at I6 to iitsnugly within and cling to the inner surface of the casing I5 and, ifdesired, the enlarged portion I6 may be cemented or otherwise secured tothe casing. Rearwardly of the enlarged front end I6, the sac is adaptedto be distended to substantially i'lll the interior of the casing whenthe sac is filled with ink, as shown in Figs. e and 5. In order that airwithin the casing externally of the sac may be discharged to preventbuilding up excessive pressure Within the casing during filling, thelatter is provided with a vent opening I'I at its rear end. Thus, ztheinterior of the casing is maintained at atmospheric pressure.

If desired, the casing I5 may be 'orrnedwithout any vent opening. Insuch construction, the distention of the sac I4 when ink is insertedtherein, in iilling, compresses the air which is in the (casingl'5surroundingthe sac I4. The air thus compressed in the casing I5aids'in maintaining a #pressure on'the'ink in the-sac I 4 and incollapsing the sac IA. behind the ink-asink vis withdrawnlin writing, tothereby maintain a continuous column of ink from the sac I4-to the ballill.

-I'fY desired, -the -front -end of the sac may be lfrictionallyfttedintothe front end of the casing I5 so that air may escape past theien'largedand When so distended, ink Within the sac is under a slightpressuredueto the -resilience of the material of VWhich the sac is Iformed, andlsuch resilience 'tends -to lforce ink from the sac through an orifice25 in thefenlarged portion fI'S whenthe cartridge is connected-with thepassage I2. In korder to `cause the rear or closed end oflthe sac'to beemptied first, thesac may'have a thicknessgraduallyincreasingtoward :itsrear end, as is apparent inFig. 2, so that the rearfend willtend tocontract rst and thus Vforce the ink 'forwardly in the sac toward the'orifice 253. 'During discharge of inkjthe vent I'I permits freeflow'o'f air'into the casing I5 so that there willbefno tendency toform-a vacuumvtherein and thus reduce -theeffectiveness of theresiliency or" thelsae'the barrel I3, of course,`having a similar-vent|9.

The enlarged front-end I5 of -the sac is so formed th'at it'ten'ds ltofiirmly close the oriiice and thus prevent inkleaking from the sacduring handling of the cartridge. However, to insure against -any suchleakage, the casing Iii may be preifidod with a cap 2l tting over theend of the casing I5-and provided with a central 1stem '22lada'pted toeXtendinto-the orice'Zand maintain lit slightly distended. Thus, theresiliencel of the enlarged front end I6 causes the material thereof 5tohug tightly about 'the stem 22 and lprevent anyleakage of ink from thecartridge during handling of it fromthe time of manufactureito the timeof use.

"-When the user desires to insert a cartridge of thischaracterinhiswritinginstrument, he separatesthe barrel I3 from vthe tip I I. The oldcartridge within Athe barrel may'then be removed vand a new oneinserted, the cap 2I having been removed from the new cartridge beforesuch insertion. During "the period after this cap vis removed and beforethe cartridge is secured in place in the writing instrument, no leakagethrough the orifice can occur since'the resilience of theenlar'ged"portion I6 causes the orifice to be closed. Afterthe cartridge has beeninserted in'thebarrel I.3,'thewriting tip I'I is screwed into the barrel`and a tubular extension -`23 `on the writing tip II is forced into theorice to place the feed passage I2 in direct communication with theinterior of the sac. Thus, ink will be fed from the sac by the tendencythereof to collapse, so that the ink is supplied to the ball I0 throughthe feed passage I2 under a slight pressure.

This application is a continuation-in-part of my 'applicationlSerial No.527,570, led March 22, 1944, for Ink cartridge, now abandoned.

YI claim:

1. An ink package comprising a self-collapsing resilient ink containingsac having a discharge orice, the walls of said sac increasing inthickness as the distance from said orifice increases for collapsingsaid walls progressively in a direction toward said oriiice.

2. --An ink package comprising a self-collapsing resilient inkcontaining sac provided with an orifice defining portion which isself-closing due to the contractile action of the resilient materialsurrounding tliefori'lce.

3. An ink cartridge comprising'a rigid tubular casing vopen at one end,and a self-contracting ink containing sac positioned in said casing andhaving ascii-closing orifice at said open endof said casing.

'4. V-`,In a writing instrument having a ball Atype writing element, arigid casing, a iiexible, re-

silient and self-collapsible ink vcontaining sac within said casing andyhaving a dischargeorifice linone end'thereoL-and means'including an ink-feed member having an ink Iflow duct therein connectingsaid dischargeoriiice'ofsaid'sac with lsaidivriting element, the 'resilience oisaidsac constantly exerting a collapsing action-on the sac creating apressure-tending to discharge ink through said orice and connectingmeans-tothe writing element, said sac being self-pressuringV`substantially throughout pr'essuring, resilient and -flexible wallmember hai-.fing a Viirst surface in contact with the link and a ventpassage-in saidl casingfor maintaining atmospheric pressure againstasecond surface of said wall member.

6. An ink package comprising'a rigid casing for containing a supply ofrelatively thick, viscous ink, and aself-'pressuring resilient,'ilexiblewall member insaid casing in contact withand conforming to the ink anddistorted thereby, the resiliency'of said wallmember serving .tofcauseit to constantly exert a'pressurezon said inkiwhich tends todischarge itfrom said package.

7. In a ball-pointed penemploying viscous inks comprising aWritingrball, a socketfor said ball, and an ink reservoir connectedthereto, said reservoir comprising a sac composed of resilient, iiexiblematerial, the wall of said sac being normally collapsed but expandedwhen ink is forced into said sac, the resiliency of said Wall, `when theWallis thus expanded, automaticallycausing said wall to exert a pressureon said ink throughout substantially .the entire ,collapsing action ofthe wall tending toiforce said inktoward said Writing ball.

V.An inkcartridge adapted .to Yserve as` areseryvoir for containingviscous ink "for a pen having a writing point, and ink feed meansleading thereto for connecting the writing point with the ink reservoir,said cartridge comprising a rigid elongate easing, means maintaining theink constantly under at least atmospheric pressure including a iiexiblesac member mounted in said easing and having an open end adapted foroperative connection With the ink feed means, said sac member having animperforate selfcollapsing wall which shuts oi the ink therein from theatmosphere and which is constantly engaged with the ink by itsself-collapsing action to avoid the formation of a sub-atmosphericpressure Within the sac member behind the ink therein and constantlyinsure a continuous column of ink from the rear or closed end of saidsac membei' to the ink feed means.

9. In a writing instrument, a rigid casing, a Writing element, means forsupporting said writing element and providing an ink feed passageleading to said Writing element, and means including an imperforateflexible and resilient wall member in said casing for sealing a. body ofink against contact with air, said wall member being distorted by theink and by reason of its resilience and flexibility conforming to saidbody of ink and constantly exerting a pressure in excess of atmosphericpressure on said body of ink to constantiy maintain a continuous columnof ink from said casing to said writing element.

10. In a ball point writing instrument, arigid casing and a resilient,self-pressuring and selfcollapsible sac within said casing for holding asupply of viscous ink with the sac distended by the ink, the collapsingresilience of said sac being such as to cause said sac to apply at leastatmospheric pressure on the ink substantially throughout its entirecollapsing action and tending to discharge ink therefrom to the balipoint, said casing being vented to maintain the space within the casingand outside of the sac at atmospheric pressure.

KENNETH S. PARKER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS OTHER REFERENCES Ser. No. 470,091, Leeuwin(A.P.C.), published July 13, '1943.

